Many caps or other closures are available for containers containing hazardous substances that are to be kept out of reach of children. These caps typically twist onto screw threads of the containers and can be twisted off or can be twisted to open positions, but include mechanisms that prevent the caps from being twisted until some release actions have been performed. The release actions are usually too complex or require too much force for small children to be able to perform them, with the result that small children are unable to open these caps. However, these caps are only resistant to opening once the caps have been closed properly, which requires effort from an adult. Further, not only children find it difficult to open these caps, but some adults such as the elderly, people with arthritis, etc, struggle to open the caps and often remove substances from containers with conventional closures—where children can access them.
Many liquid preparations such as medicines for infants can be metered and/or administered conveniently by using a syringe without a needle, but in order to draw the preparation into the syringe, the container containing the preparation needs to be opened and needs to be kept open. Further, the tasks of drawing a liquid preparation from a container into a syringe and administering this to an infant and at the same having to handle the container and possibly also the infant, can be too much for a single person. The result is that containers are often opened for drawing a liquid preparation from the container and are then left open until the preparation has been administered and the infant tended, before the cap is replaced on the container. In many instances, the adult may be delayed in closing the container, e.g. if the infant requires considerable attention, with the result that the container remains open for an extended period and can be accidentally knocked over and/or could be taken by a child in the vicinity.
The problem of containers remaining open while their liquid contents are being dispensed, is not limited to metering/administration of medicines with syringes, but also occurs when the contents need to be poured, or dispensed in any other way.
Attempts have been made to address the difficulties of containers remaining open, by providing containers that open against resistance and close automatically. However, containers of this type are very inconvenient for dispensing liquids with a syringe, as it is very difficult to handle a syringe with one hand, while keeping the container open with another.
Most so-called “child-safe” container caps are twisted onto screw threads of the containers and while their release actions may be too complex for children, the children are able to open the containers by twisting the caps with enough force. It is possible also for adults who struggle with the caps or are momentarily mistaken about their operation, to apply twisting force that could break or overcome their features resisting unauthorised opening.
The present invention seeks to provide a closure for a container that resists access to its contents by small children at all times when not handled by an adult, yet allows its contents to be drawn conveniently into a syringe and/or to be poured. Further, the invention seeks to provide a closure that resists spillage and/or that resists breakage in the event that excessive twisting force is applied to it.